Power tool accessory attachment system

ABSTRACT

A power tool is provided and may include a motor, an output shaft, a neck portion, and a collar portion. The output shaft may be driven by the motor. The neck portion may be configured to receive a removable attachment accessory. The neck portion may define a first diameter and may include a plurality of indexing features. The collar portion may be supported by the neck portion. The collar portion may include an outer circumferential surface defining a second diameter that is greater than the first diameter. The outer circumferential surface may include at least one recess.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/005,194, filed on May 30, 2014, and U.S. Provisional Application No.62/028,839, filed on Jul. 25, 2014. The entire disclosures of each ofthe above applications are incorporated herein by reference.

FIELD

The present disclosure relates to a power tool accessory attachmentsystem, and more particularly to a system suitable for use in securingan accessory head to a power tool such as a drill or driver.

BACKGROUND

This section provides background information related to the presentdisclosure and is not necessarily prior art.

Various types of power tools are designed for use with variousinterchangeable accessories or accessory heads. For example,electrically powered multi tools can commonly be used to operate asanding accessory head, a cutting accessory head, and a drilling/drivingaccessory head. The accessory heads can be attached to the multi toolbody. When working with a power tool and an accessory head, it may bedesirable to provide an accessory attachment system that allows a userto easily attach and/or remove the accessory head from the power tool,while also allowing the user to index, or otherwise rotate the accessoryrelative to the power tool.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

According to one particular aspect, the present disclosure provides apower tool. The power tool may include a motor, an output shaft, a neckportion, and a collar portion. The output shaft may be driven by themotor. The neck portion may be configured to receive a removableattachment accessory. The neck portion may define a first diameter andmay include a plurality of indexing features. The collar portion may besupported by the neck portion. The collar portion may include an outercircumferential surface defining a second diameter that is greater thanthe first diameter. The outer circumferential surface may include atleast one recess.

In some configurations, the at least one recess is aligned with one ofthe plurality of indexing features.

In some configurations, the collar has at least two recesses.

In some configurations, the at least two recesses are disposed onopposite sides of the collar.

In some configurations, the plurality of indexing features comprises aplurality of recesses separated by peripheral surface portions.

In some configurations, the power tool includes a removable attachmentaccessory. The removable attachment accessory includes a retainer havinga radially inwardly extending key feature and the plurality of indexingfeatures are configured to selectively engage the key feature.

In some configurations, the recess is configured to allow the keyfeature to be moved past the collar.

In some configurations, the power tool is a drill or a screwdriver.

In some configurations, the retainer is a biasing member.

In some configurations, the biasing member is a leaf spring.

In some configurations, the biasing member is substantially U-shaped.

In some configurations, the key feature includes a substantiallyU-shaped lobe.

In some configurations, the key feature includes a substantiallyhemispherical detent.

In some configurations, the accessory includes a housing having firstand second clamshells. The first clamshell includes first and secondpockets. The second clamshell includes third and fourth pockets that arealigned with the first and second pockets, respectively. The retainerincludes a first member at least partially disposed in the first andsecond pockets, and a second member at least partially disposed in thethird and fourth pockets.

In some configurations, the first and second members are leaf springs.

In some configurations, the accessory includes a hub and a collarslidably supported by the hub.

In some configurations, the collar includes a radially inwardlyextending lock portion operable to lock the retainer in a firstposition.

In some configurations, the retainer includes a substantially sphericalmember.

In some configurations, the retainer is monolithically formed with thecollar.

In some configurations, the retainer is resiliently flexible.

In some configurations, the hub includes an axially extending channeland a circumferentially extending channel. The retainer is disposed inthe circumferentially extending channel and the collar includes a lockportion slidably disposed in the axially extending channel.

In some configurations, the power tool includes a first axis ofrotation, and the accessory includes a tool having a second axis ofrotation. The first and second axes of rotation define a plane. The keyfeature is offset from the plane by an angle.

In some configurations, the angle is between ten degrees and eightydegrees.

In some configurations, the angle is substantially equal to forty-fivedegrees.

In some configurations, the accessory includes a housing having firstand second clamshells, the first and second clamshells including firstand second mating surfaces, respectively, and wherein the key feature isoffset from at least one of the first and second mating surfaces by anangle.

According to another particular aspect, the present disclosure providesa power tool accessory. The power tool accessory may include a housingand a retainer. The housing may define an inner chamber and may beconfigured for removably coupling the accessory to a power tool. Theretainer may be disposed within the inner chamber and may include aninwardly projecting key feature configured to engage the power tool.

According to yet another particular aspect, the present disclosureprovides a power tool. The power tool may include a housing, an outputshaft and an accessory. The housing may include a neck portion and acollar portion. The neck portion may include a first outer surfacedefining a first diameter and having a plurality of indexing featuresformed therein. The collar portion may include a second outer surfacedefining a second diameter greater than the first diameter. The outputshaft may be supported by the housing and define an axis of rotation.The accessory may be removably coupled to the output shaft and mayinclude a retainer. The retainer may include a radially inwardlyextending key feature disposed between the housing and the collar. Thekey feature may be configured to engage one of the plurality of indexingfeatures to allow the accessory to rotate about the axis of rotation.

According to yet another particular aspect, the present disclosureprovides a method of attaching an attachment accessory to a power toolpower. The power tool may include a motor and an output shaft driven bythe motor. The power tool may further include a neck portion defining afirst diameter, a collar portion having an outer circumferential surfacedefining a second diameter greater than the first diameter, and a recessin the outer circumferential surface. The attachment accessory mayinclude a retainer with a key feature. The method may include aligningthe key feature with the recess. The method may further include movingthe attachment accessory towards the power tool so that the key featurepasses past the collar portion through the recess. The method may alsoinclude rotating the attachment accessory so that the key feature is nolonger aligned with the recess and the collar portion restricts movementof the attachment accessory away from the power tool. In someconfigurations, the attachment accessory may further include a movablelock portion which can be moved into a locking position to restrictmovement of the key feature. The method may further include moving thelock portion to the locking position after the rotating the attachmentaccessory so that the key feature is no longer aligned with the recess.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is an exploded view of a power tool and a power tool accessory inaccordance with the principles of the present disclosure;

FIG. 2 is a partial perspective view of the power tool and power toolaccessory system of FIG. 1 with a portion of the accessory removed forclarity;

FIG. 2A is a partial perspective view of the power tool accessory ofFIG. 1;

FIG. 3 is a perspective view of a portion of another power toolaccessory in accordance with the principles of the present disclosure;

FIG. 4 is a cross-sectional view of the power tool accessory of FIG. 3,taken through the line 4-4;

FIG. 5 is an exploded perspective view of the power tool accessory ofFIG. 3;

FIG. 6 is a partial perspective view of another power tool accessory inaccordance with the principles of the present disclosure;

FIG. 7 is an exploded perspective view of a portion of another powertool accessory in accordance with the principles of the presentdisclosure;

FIG. 8 is a partial cross-sectional view of another power tool accessoryin accordance with the principles of the present disclosure;

FIG. 9 is an end view of a portion of another power tool accessory inaccordance with the principles of the present disclosure;

FIG. 10 is an exploded view of another power tool accessory inaccordance with the principles of the present disclosure;

FIG. 11 is an end view of the power tool accessory of FIG. 10;

FIG. 12A is a cross-sectional view of the power tool accessory of FIG.10 in a first position;

FIG. 12B is a cross-sectional view of the power tool accessory of FIG.10 in a second position;

FIG. 13 is an exploded view of another power tool accessory inaccordance with the principles of the present disclosure;

FIG. 14 is an end view of the power tool accessory of FIG. 13;

FIG. 15A is a cross-sectional view of the power tool accessory of FIG.13 in a first position;

FIG. 15B is a cross-sectional view of the power tool accessory of FIG.13 in a second position;

FIG. 16 is an exploded view of another power tool accessory inaccordance with the principles of the present disclosure;

FIG. 17 is an end view of the power tool accessory of FIG. 16;

FIG. 18A is a cross-sectional view of the power tool accessory of FIG.16 in a first position; and

FIG. 18B is a cross-sectional view of the power tool accessory of FIG.16 in a second position.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings. The terminology used herein is for thepurpose of describing particular example embodiments only and is notintended to be limiting. As used herein, the singular forms “a,” “an,”and “the” may be intended to include the plural forms as well, unlessthe context clearly indicates otherwise. The terms “comprises,”“comprising,” “including,” and “having,” are inclusive and thereforespecify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof. The method steps,processes, and operations described herein are not to be construed asnecessarily requiring their performance in the particular orderdiscussed or illustrated, unless specifically identified as an order ofperformance. It is also to be understood that additional or alternativesteps may be employed.

When an element or layer is referred to as being “on,” “engaged to,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present. In contrast,when an element is referred to as being “directly on,” “directly engagedto,” “directly connected to,” or “directly coupled to” another elementor layer, there may be no intervening elements or layers present. Otherwords used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.). As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer or section from another region,layer or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer or section discussed below could be termed a second element,component, region, layer or section without departing from the teachingsof the example embodiments.

Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,”“lower,” “above,” “upper,” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Spatiallyrelative terms may be intended to encompass different orientations ofthe device in use or operation in addition to the orientation depictedin the figures. For example, if the device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

With reference to FIGS. 1 and 2, a power tool 12 and a power toolaccessory 14 are provided in accordance with the principles of thepresent disclosure. While the power tool 12 shown in the figures is apower drill, the power tool 12 can be any other type of power tool suchas a multi tool, a screwdriver, an impact driver, a hammer drill, or asander, for example.

The power tool 12 may include a housing 16 which surrounds a motor 18.The housing 16 includes a handle 20 which may engage a power source (notshown) coupled with the handle. The power source may be a battery, an ACcord, a pneumatic line, or other suitable power source otherwise knownin the art. An activation member (e.g., a trigger or switch) 23 iselectrically coupled with the motor 18 and the power source. Theactivation member 23 energizes and de-energizes the motor 18. The motor18 may be drivingly coupled with a gear system (not shown) thattransmits power to an output shaft 25.

The gear system may be surrounded by a gear case 28 and may drive theshaft 25 to rotate about an axis 26. As illustrated in FIGS. 1 and 2,the gear case 28 may include a body portion 30, a neck portion 32 and aflange or collar portion 34. While the body, neck and collar portions30, 32, 34 of the gear case 28 are described as being separate elementsof the gear case 28, it will be appreciated that the body, neck andcollar portions 30, 32, 34 may be a monolithic construct within thescope of the present disclosure. The body portion 30 may extend from thehousing 16 and may include a first stop surface 35 defining a firstwidth or diameter OD1. The neck portion 32 may extend from the bodyportion 30, and may define a substantially cylindrical construct havinga second diameter OD2 that is smaller than the first diameter OD1. Aperipheral surface 36 of the neck portion 32 may include a plurality ofequally sized and spaced indexing features 38, defining an annularspline configuration. In some configurations, the indexing features 38may include substantially semi-cylindrical detents, each defining aradius R1. It will be appreciated, however, that the indexing features38 may have other shapes (e.g., hemispherical) within the scope of thepresent disclosure.

The collar portion 34 of the gear case 28 may extend from the neckportion 32. The collar portion 34 may define a substantially cylindricalconstruct having a third diameter OD3 that is greater than the seconddiameter OD2 of the neck portion 32. In this regard, the neck portion 32may define an annular groove or channel between the collar portion 34and the first stop surface 35. The collar portion 34 may further includea second stop surface 40, one or more detents or recesses 42, aperipheral surface 43, and a tapered or chamfered leading edge 45 (FIG.2). The second stop surface 40 may oppose the first stop surface 35. Therecess 42 may be formed in, and extend radially into, the peripheralsurface 43 of the collar portion 34. As illustrated in FIG. 2, therecess 42 may be substantially semi-cylindrical and may have a radiusR2. As illustrated, in some configurations, the collar portion 34 mayinclude two recesses 42. It will be appreciated, however, that thecollar portion 34 may include more or less than two recesses 42 withinthe scope of the present disclosure. Each of the recesses 42 may besubstantially aligned with one of the indexing features 38. In someconfigurations, the radius R1 of the indexing features 38 may besubstantially equal to the radius R2 of the recesses 42. The chamferedleading edge 45 may extend from and between the second stop surface 40and the peripheral surface 43.

Referring now to FIGS. 1 and 2, the accessory 14 may include a housing44, a tool subassembly 46 and one or more retainers 48. As will bedescribed in more detail below, the accessory 14 may be mounted orotherwise coupled to the gear case 28 and/or the housing 16 of the powertool 12, such that rotation of the shaft 25, in turn, drives themovement (e.g., rotation) of the tool subassembly 46. While the toolsubassembly 46 is illustrated as a being a right angle drill/driver, itwill be appreciated that the tool subassembly 46 may have otherconfigurations (e.g., a corkscrew, saw, sander, etc.) within the scopeof the present disclosure.

The housing 44 may include first and second clamshells 50, 52, that maybe fastened together by screws 53 or other fasteners or by a snap fit,for example. The second clamshell 52 may be substantially similar to thefirst clamshell 50. Accordingly, except as otherwise provided,references to the first clamshell 50 will be understood to apply equallyto the second clamshell 52, and like reference numerals will be usedhereinafter and in the drawings to identify similar features andcomponents on both the first and second clamshells 50, 52.

As shown in FIG. 2, the first and second clamshells 50, 52 may eachinclude first and second mating surfaces 54, 56, such that a sidewall 60of the first and second clamshells define a cutout portion or chamber 58(FIG. 1). As will be explained in more detail below, in an assembledconfiguration, the chamber 58 receives a portion of the power tool 12and/or the tool subassembly 46. The sidewall 60 of the first clamshell50 may define a third stop surface 62, and may further include a grooveor channel 64 and an annular rib or flange 66. As shown in FIGS. 2 and2A, the channel 64 may include a plurality of radially outwardlyextending apertures 67 and radially inwardly extending projections 68each having flanged or lipped ends 70. Each of the projections 68 may bedisposed between a pair of the threaded apertures 67. The flange 66 maydefine a fourth stop surface 72 abutting the second stop surface 40(FIG. 2) of the collar portion 34.

In one configuration, the retainers 48 may be or include biasingmembers, such as leaf springs. In this regard, the retainers 48 may beconstructed of spring steel, or any other resiliently flexible material.The retainers 48 may include forked ends 76, 78 and a lobe or keyfeature 80 therebetween. As illustrated in FIGS. 1 and 2, in theassembled configuration, the accessory 14 may include two retainers 48,each disposed within the channel 64 of the respective first and secondclamshells 50, 52. The retainers 48 may be disposed within the channel64 such that the key feature 80 substantially straddles the projection68, and the lipped ends 70 abut opposing sides of the key feature 80(FIGS. 2 and 2A). With reference to FIGS. 1 and 2A, in someconfigurations, screws 82, bolts, or other similar mechanical fastenersengage threaded apertures 67 to secure the forked ends 76, 78 of theretainers 48 to the first and second clamshells 50, 52.

The tool subassembly 46 may be coupled or otherwise mounted to thehousing 44. As illustrated in FIG. 1, a right angle drill toolsubassembly 46 may include a first gear member 83 a, a second gearmember 83 b, a first bearing assembly 84 a, and a second bearingassembly 84 b. The first and second bearing assemblies 84 a, 84 b may bemounted within the housing 44.

The first gear member 83 a may be rotatably coupled to the first bearingassembly 84 a, and may include a first spindle portion 85 a and a firstgear portion 87 a. The first spindle portion 85 a may extend into thechamber 58 of the housing 44, and may be sized and shaped to mate withthe shaft 25 of the power tool 12, such that the shaft 25 can drive therotation of the first gear member 83 a. In this regard, in oneconfiguration, the shaft 25 may include a hexagonal socket, and thefirst spindle portion 85 a may define a hexagonal cross sectionsimilarly sized and shaped as the hexagonal socket.

The second gear member 83 b may be rotatably coupled to the secondbearing assembly 84 b, and may include a second spindle portion 85 b anda second gear portion 87 b. In an assembled configuration, the firstgear portion 87 a may be meshingly engaged with the second gear portion87 b, such that rotation of the first gear portion 87 a drives therotation of the second gear portion 87 b. As illustrated, a tool 89,such as a drill bit or screwdriver, can be coupled to the second gearmember 83 b. As previously noted, while the tool subassembly 46 isdescribed and illustrated herein as being a right angle drillsubassembly, it will appreciated that the tool subassembly 46 mayinclude other configurations that can be coupled to and driven by theshaft 25, within the scope of the present disclosure.

In operation, the accessory 14 can be assembled to the power tool 12 byaligning the key features 80 of the retainers 48 with correspondingrecesses 42 of the collar portion 34, and pushing or otherwise movingthe accessory 14 along the axis 26 relative to the power tool 12 untilthe retainers 48 are aligned with the neck portion 32, and the shaft 25is coupled to the first spindle portion 85 a of the first gear member 83a. To lock the accessory 14 to the power tool 12, the user can rotatethe accessory 14 about the axis 26, such that key features 80 are notaligned with the recesses 42. In this regard, the key features 80 may berotated into alignment with one of the indexing features 38, such thatthe user can change the position of the tool subassembly 46 relative tothe power tool 12 by selecting a desired indexing feature 38, orcombination of indexing features, to receive the key features 80 of theretainer 48. In the assembled configuration, the third stop surface 62may abut the first stop surface 35, and the fourth stop surface 72 mayabut the second stop surface 40 (FIG. 2).

When the user rotates the accessory 14 relative to the power tool 12,the retainers 48 resiliently flex outward and inward as the key features80 respectively disengage and engage the indexing features 38. Theinward biasing force of the retainers 48 keep the key features 80removably engaged with corresponding indexing features 38. To rotate orindex the accessory 14 relative to the power tool 12, the user mustovercome the spring force of the retainers 48 to disengage the keyfeatures 80 from indexing features 38 as the key features 80 are movedbetween adjacent indexing features 38. To remove the accessory 14 fromthe power tool 12, the user can rotate the accessory 14 about the axis26 such that the key features 80 are aligned with the recesses 42 in thecollar portion 34. Once the key features 80 are aligned with therecesses 42, the user can slide the accessory 14 along or parallel tothe axis 26 to remove the accessory 14 from the power tool 12.

With reference to FIGS. 3-5, another accessory 14 a is provided that maybe used with the power tool 12 instead of the accessory 14. Theaccessory 14 a may include a housing 44 a and one or more retainers 48a. The structure and function of the housing 44 a and the retainers 48 amay be similar or identical to the structure and function of the housing44 and the retainer 48 described above, apart from any exceptionsdescribed below and/or shown in the figures. Accordingly, similarfeatures will not be described again in detail. Like reference numeralsare used hereinafter and in the drawings to identify like componentswhile like reference numerals containing letter extensions are used toidentify those components that have been modified. While not necessarilyshown in FIGS. 3-5, it will be appreciated that the housing 44 a may beshaped, sized and/or otherwise configured to accommodate any shafts,gears, tools and/or other features of a given type of accessory. It willalso be appreciated that the retainers 48 a may be used with the housing44, and the housing 44 a may be used with the retainers 48.

The mating surfaces 54 a, 56 a of the first clamshell 50 a may eachinclude a first pocket 86, and the mating surfaces 54 a, 56 a of thesecond clamshell 52 a may each include a second pocket 88. The first andsecond pockets 86, 88 may include first surfaces 90, 92, respectively,generally facing the chamber 58, and second surfaces 94, 96,respectively, generally facing the first surfaces 90, 92. The firstsurfaces 90, 92 may have a concave profile, while the second surfaces94, 96 may have a substantially planar profile. In an assembledconfiguration, the mating surfaces 54 a, 56 a of the first clamshellportion 50 a may be coupled to the mating surfaces 54 a, 56 a,respectively, of the second clamshell portion 52 a. In the assembledconfiguration, the first surfaces 90, 92 of the first clamshell portion50 a may define a contiguous arc with the first surfaces 90, 92,respectively, of the second clamshell portion 52. The second surfaces94, 96 of the first and second clamshell portions 50 a, 52 a may definewindows or apertures 98 respectively, therebetween.

Each retainer 48 a may include a key feature 80 a. As illustrated, thekey feature 80 a may define a portion of a sphere, for example. In thisregard, in some configurations, the key feature 80 a defines asubstantially hemispherical detent. As illustrated in FIG. 4, in theassembled configuration, the ends 76 a, 78 a of the retainer 48 a may bedisposed within the first and second pockets 86, 88 of the first andsecond clamshells 50 a, 52 a, respectively, such that the key features80 a are aligned with, and extend through, the apertures 98.

To assemble the accessory 14 a onto the power tool 12, the user may movethe accessory 14 a along the axis 26 until the key features 80 acontacts the collar portion 34 of the power tool 12. As the usercontinues to move the accessory 14 a along the axis 26, the collarportion 34 may slide along the key feature 80 a, biasing the key feature80 a in a direction substantially perpendicular to the axis 26. In thisregard, the retainer 48 a may conform to the shape or profile of thefirst surfaces 90, 92 of the first and second pockets 86, 88. Once thekey feature 80 a has moved sufficiently past the collar portion 34, theretainer 48 a may resiliently return to its original configuration (FIG.4), such that the key feature 80 a is disposed between the first andsecond stop surfaces 35, 40 and within one of the indexing features 38.

With reference to FIG. 6, another accessory 14 b is provided that may beused with the power tool 12 instead of the accessory 14. The accessory14 b may include a housing 44 b and a retainer 48 b. The structure andfunction of the housing 44 b and the retainer 48 b may be similar oridentical to the structure and function of the housing 44 and theretainer 48 described above, apart from any exceptions described belowand/or shown in the figures. Accordingly, similar features will not bedescribed again in detail. Like reference numerals are used hereinafterand in the drawings to identify like components while like referencenumerals containing letter extensions are used to identify thosecomponents that have been modified. While not necessarily shown in FIG.6, it will be appreciated that the housing 44 b may be shaped, sizedand/or otherwise configured to accommodate any shafts, gears, toolsand/or other features of a given type of accessory. It will also beappreciated that the retainer 48 b may be used with any of the housingsdescribed herein, and the housing 44 b may be used with any of theretainers described herein.

The first clamshell 50 b and the second clamshell (not shown) may eachinclude a channel 64 b. The channel 64 b may include a pair of teeth orheat stake elements 102 extending in a direction substantiallyperpendicular to the axis 26. The retainer 48 b may include a pair ofapertures 103. In an assembled configuration, the heat stake elements102 may extend through the apertures 103. The heat stake elements 102may then be melted to secure the retainers 48 b to the first and secondclamshells 50 b, 52 b.

With reference to FIG. 7, another accessory 14 c is provided that may beused with the power tool 12 instead of the accessory 14. The accessory14 c may include the housing 44 b and a retainer 48 c. The function ofthe retainer 48 c may be generally similar to the function of theretainer 48 described above, apart from any exceptions described belowand/or shown in the figures. While the accessory 14 c is shown in FIG. 7as including the housing 44 b, it will also be appreciated that theretainer 48 c could, alternatively, be used with either of the housings44, 44 a, for example.

The retainer 48 c may be formed into a substantially circular or ringshape extending between first and second ends 104, 106. The retainer 48c may have an inner diameter ID4 that is substantially equal to, butslightly greater than, the third diameter OD3 of the collar portion 34of the power tool 12 (FIG. 1). The retainer 48 c may further include aninwardly projecting, annular key feature 80 c. The key feature 80 c maydefine a radially extending projection on an inner surface 107 of theretainer 48 c. As illustrated, in some configurations, the key feature80 c defines a substantially semi-cylindrical projection.

When the first clamshell portion 50 a is assembled to the secondclamshell portion 52 a, the retainer 48 c may become trapped orotherwise secured within the channel 64 c. To assemble the accessory 14c onto the power tool 12, the user may move the accessory 14 c along theaxis 26 until the key feature 80 c contacts the collar portion 34 of thepower tool 12. As the user continues to move the accessory 14 c alongthe axis 26, the collar portion 34 may slide along the key feature 80 c,urging the key feature 80 c radially outward in a directionsubstantially perpendicular to the axis 26, such that the first end 104moves away from the second end 106 to increase the inner diameter ID4.Once the key feature 80 c has moved sufficiently past the collar portion34, the retainer 48 c may resiliently return to its originalconfiguration, such that the key feature 80 c is disposed between thefirst and second stop surfaces 35, 40. Interference between the keyfeature 80 c and the collar portion 34 prevents the accessory 14 c fromsliding off of the power tool 12 within application of sufficient forceto cause key feature 80 c to expand outward to a sufficient extent toallow removal of the accessory 14 c from the power tool 12.

With reference to FIG. 8, another accessory 14 d is provided that may beused with the power tool 12 instead of the accessory 14. The accessory14 d may include a housing 44 d and a retainer 48 d. The structure andfunction of the housing 44 d and the retainer 48 d may be similar oridentical to the structure and function of the housing 44 and theretainer 48 described above, apart from any exceptions described belowand/or shown in the figures. Accordingly, similar features will not bedescribed again in detail. Like reference numerals are used hereinafterand in the drawings to identify like components, while like referencenumerals containing letter extensions are used to identify thosecomponents that have been modified.

The housing 44 d may include an aperture 106 extending in a radialdirection substantially perpendicular to the axis 26. A button assembly109 may be disposed within the aperture 106. The button assembly 109 mayinclude a button 110 and a biasing member 112. The button 110 mayinclude a stem portion 114 and a tip 116. In an assembled configuration,the stem portion 114 may be disposed within the aperture 106. The tip116 may be generally wedge shaped. The biasing member 112 may be ahelical spring concentrically disposed about the stem portion 114.

The retainer 48 d may be formed into a generally rectangular shapeextending between first and second arcuately extending ends 118 d, 120d. The retainer 48 d may define an inner width W1 that is less than thethird diameter OD3 of the collar portion 34 of the power tool 12. Whenclamshell portions of the housing 44 d are assembled together aspreviously described, the first and second ends 118 d, 120 d may besubstantially aligned with the aperture 106 and with the tip 116 of thebutton 110. To assemble the accessory 14 d onto the power tool 12, theuser may move the accessory 14 d along the axis 26 until the retainer 48d contacts the collar portion 34 of the power tool 12. The user may thenpress the button 110 such that the tip 116 contacts, and extendsbetween, the first and second ends 104 d, 106 d, thereby causing thefirst end 104 d to move away from the second end 106 d. As the first end104 d moves away from the second end 106 d, the width W1 of the retainer48 d will increase such that the width W1 is greater than the thirddiameter OD3 of the collar portion 34, thereby allowing the user to movethe retainer 48 d into alignment with the annular groove or channeldefined by the neck portion 32 of the gear case 28. Once the userreleases the button 110, the biasing member 112 can bias the tip 116 outof engagement with the first and second ends 104 d, 106 d of theretainer 48 d. In this regard, the retainer 48 d may resiliently returnto its original configuration such that the retainer 48 d is disposedand secured between the collar portion 34 and the body portion 30 of thegear case 28 in a manner that restricts the accessory 14 d from slidingoff of the power tool 12. To release the accessory 14 d from the powertool 12, the user may press the button 110 such that the tip 116increases the width W1 so that the width W1 is larger than the thirddiameter OD3 of the collar portion 34 in the manner described above,thereby allowing the retainer 48 d to slide past the collar portion 34.

With reference to FIG. 9, another accessory 14 e is provided that may beused with the power tool 12 instead of the accessory 14. The accessory14 e may include a retainer 48 e. The structure and function of theretainer 48 e may be similar or identical to that of the retainer 48 ddescribed above, apart from any exceptions described below and/or shownin the figures. Therefore, similar features will not be described againin detail. It will also be appreciated that the retainer 48 e may beused with any of the housings 44, 44 a, 44 b described herein.

The retainer 48 e may include opposed key features 80 e. In operation,the accessory 14 e can be assembled to the power tool 12 by aligning thekey features 80 e of the retainer 48 e with the recesses 42 formed inthe collar portion 34, and pushing or otherwise moving the accessory 14e along the axis 26 until the retainer 48 e is aligned with the neckportion 32. To lock the accessory 14 e to the power tool 12, the usercan rotate the accessory 14 e about the axis 26, such that key features80 e are not aligned with the recesses 42. In this regard, the keyfeatures 80 e may be rotated into alignment with one of the indexingfeatures 38, such that the user can change the position of the toolsubassembly 46 relative to the power tool 12 by selecting a desiredindexing feature 38, or combination of indexing features, to receive thekey features 80 e of the retainer 48. To remove the accessory 14 e fromthe power tool 12, the user can rotate the accessory 14 e about the axis26 such that the key features 80 e are aligned with the recesses 42 inthe collar portion 34. Once the key features 80 e are aligned with therecesses 42, the user can move the accessory 14 e along or parallel tothe axis 26 to remove the accessory 14 e from the power tool 12.

With reference to FIGS. 10-12B, another accessory 14 f is provided thatmay be used with the power tool 12 instead of the accessory 14. Theaccessory 14 f may include a housing 44 f, one or more retainers 48 f,and a collar 128. The structure and function of the housing 44 f and theretainers 48 f may be similar or identical to the structure and functionof the housing 44 and the retainer 48 described above, apart from anyexceptions described below and/or shown in the figures. Accordingly,similar features will not be described again in detail. Like referencenumerals are used hereinafter and in the drawings to identify likecomponents while like reference numerals containing letter extensionsare used to identify those components that have been modified. While notnecessarily shown in FIGS. 10-12B, it will be appreciated that thehousing 44 f may be shaped, sized and/or otherwise configured toaccommodate any shafts, gears, tools and/or other features of a giventype of accessory.

The housing 44 f may include first and second clamshells 50 f, 52 f,that may be fastened together by a clip 53 f, other fasteners, or by asnap fit, for example. The second clamshell 52 f may be substantiallysimilar to the first clamshell 50 f. Accordingly, except as otherwiseprovided, references to the first clamshell 50 f will be understood toapply equally to the second clamshell 52 f, and like reference numeralswill be used hereinafter and in the drawings to identify similarfeatures and components on both the first and second clamshells 50 f, 52f.

The first clamshell 50 f may include a hub portion 130 having a first orproximal end 132 and a second or distal end 134. In some configurations,the hub portion 130 may include a generally cylindrical constructextending axially from and between the proximal and distal ends 132,134. The proximal end 132 may be integrally formed with the housing 44f. The distal end 134 may include a third stop surface 62 f.

The hub portion 130 may further include an inner surface 136 and anouter surface 138. The inner surface 136 may include a radially inwardlyprojecting flange 66 f and the retainer 48 f. The flange 66 f mayinclude a fourth stop surface 72 f. The retainer 48 f may be locatedbetween the flange 66 f and the distal end 134 of the hub portion 130and may include a radially inwardly projecting key feature 80 f and alock member 141. In some configurations, the accessory 14 f may includetwo retainers 48 f, including two key features 80 g and two lock members141. The key feature 80 f may include a window or aperture 142 and anaxially extending lip 146, such that the aperture 142 includes a fifthdiameter ID5, and a sixth diameter ID6 proximate to, and defined by, thelip 146. The sixth diameter ID6 may be smaller than the fifth diameterID5. The lock member 141 may be located within the aperture 142 and mayinclude a generally spherical member, such as a ball bearing, forexample. In this regard, the lock member 141 may include a diameter OD9that is larger than the sixth diameter ID6, and smaller than the fifthdiameter ID5.

The outer surface 138 of the hub portion 130 may extend axially from thehousing 44 f, such that the housing 44 f includes or otherwise defines afifth stop surface 148 at the proximal end 132 of the hub portion 130.In an assembled configuration, the fifth stop surface 148 may extendcircumferentially about the hub portion 130. The outer surface 138 mayinclude a first groove or channel 150 and a second groove or channel152. The first channel 150 may extend axially and may include a first orproximal end 153, a second or distal end 154, and an axially extendingsurface 156. The proximal end 151 may include a sixth stop surface 157(FIG. 10). The distal end 154 may open into the distal end 134 of thehub portion 130. The aperture 142 may open into the first channel 150,such that the aperture 142 is in communication with the first channel150. The axially extending surface 156 may include a convex orcylindrical profile.

The second channel 152 may extend circumferentially about the outersurface 138, and may be located proximate to the distal end 134 of thehub portion 130. In this regard, the key feature 80 f may be locatedbetween the second channel 152 and the fifth stop surface 148. Withreference to FIGS. 12A and 12B, in an assembled configuration, a ring160 may be positioned in the second channel 152. The ring 160 may extendradially outward beyond the outer surface 138, such that the ring 160includes, or otherwise defines, a seventh stop surface 162. In thisregard, it will also be appreciated that the ring 160 may also serve tosecure the first clamshell 50 f to the second clamshell 52 f.

The collar 128 may have a generally cylindrical construct including aproximal end 166, a distal end 168, an inner surface 170 and an outersurface 172. The inner surface 170 may include a first portion 171 and asecond portion 173. The first portion 171 may be a circumferential stopsurface. In this regard, the first portion 171 may include a tapered orchamfered portion. The inner surface 170 may further include a radiallyinwardly projecting lock portion 176. In this regard, the lock portion176 may project radially inwardly from the second portion 173 of theinner surface 170. As illustrated, in some configurations, the innersurface 170 may include two lock portions 176. The lock portion 176 mayextend axially from a proximal end 178 to a distal end 180 and mayinclude a ramp surface 182 and a lock surface 184. The ramp surface 182may extend axially from the distal end 180, and may taper radiallyinwardly towards the proximal end 178. In this regard, the ramp surface182 may be concave or otherwise include a cylindrical profile. The locksurface 184 may extend axially from the proximal end 178, and may beconcave or otherwise include a cylindrical profile. The ramp surface 182may join or otherwise meet the lock surface 184 between the proximal anddistal ends 178, 180 of the lock portion 176.

The outer surface 172 of the collar 128 may include a gripping member orportion 192. As illustrated, in some configurations, the grippingportion 192 may include an annular rib projecting radially outward fromthe outer surface 172. As will be explained in more detail, below, thegripping portion 192 may allow the user to securely grasp and operatethe collar 128.

In an assembled configuration, the collar 128 may be coupled to thehousing 14 f. In this regard, the collar 128 may be slidably disposedabout the hub portion 130 of the first and second clamshells 50 f, 52 f,such that the lock portion 176 is received in the first channel 150, andthe lock member 141 is secured between the lock portion 176 and the lip146 of the key feature 80 f. As will be explained in more detail below,in the assembled configuration, the collar 128 may be secured, andslidably disposed, between the fifth stop surface 148 of the housing 44f and the seventh stop surface 162 of the ring 160.

In operation, the accessory 14 f can be assembled to the power tool 12by aligning the key feature 80 f with the corresponding recess 42 of thepower tool 12, and pushing or otherwise moving the accessory 14 f alongthe axis 26 relative to the power tool 12 until the key feature 80 f isaligned with the neck portion 32 of the power tool 12. To secure theaccessory 14 f to the power tool 12, the user can rotate the accessory14 f about the axis 26, such that key feature 80 f is not aligned withthe recess 42. In this regard, the user can rotate the accessory 14 funtil the lock member 141 is aligned with one of the indexing features38, such that the user can change the position of the tool subassembly46 relative to the power tool 12 by selecting a desired indexing feature38, or combination of indexing features, to receive the lock member 141.

With the collar 128 in a first or unlocked position (FIG. 12A), the rampsurface 182 of the lock portion 176 may engage the lock member 141, suchthat the lock member 141 does not extend radially inwardly beyond thelip 146 of the key feature 80 f. In this regard, it will be appreciatedthat in the unlocked position, the accessory 14 f may be rotatable onthe power tool 12 about the axis 26. To lock the accessory 14 f relativeto the power tool 12, and thereby prevent the accessory from rotatingabout the axis 26, the user can slide or otherwise move the collar 128along the axis 26 into a second or locked position (FIG. 12B). In thelocked position, the lock surface 184 of the lock portion 176 may pushthe lock member 141 radially inwardly within the aperture 142 such thata portion of the lock member 141 extends radially inwardly beyond thelip 146 of the key feature 80 f, and into engagement with the indexingfeature 38. As illustrated, in the locked position, the collar 128(e.g., the lock portion 176) may abut the seventh stop surface 162 ofthe ring 160 to prevent the collar 128 from disengaging the hub portion130 of the housing 44 f. As will be appreciated, the user can move thecollar 128 back into the unlocked position to remove the accessory 14 ffrom the power tool 12, or rotate the accessory 14 f relative to thepower tool 12.

With reference to FIGS. 13-15B, another accessory 14 g is provided thatmay be used with the power tool 12 instead of the accessory 14. Theaccessory 14 g may include a housing 44 g and a collar 128 g. Thestructure and function of the housing 44 g and the collar 128 g may besimilar or identical to the structure and function of the housing 44 fand the collar 128 described above, apart from any exceptions describedbelow and/or shown in the figures. Accordingly, similar features willnot be described again in detail. Like reference numerals are usedhereinafter and in the drawings to identify like components while likereference numerals containing letter extensions are used to identifythose components that have been modified. While not necessarily shown inFIGS. 13-15B, it will be appreciated that the housing 44 g may beshaped, sized and/or otherwise configured to accommodate any shafts,gears, tools and/or other features of a given type of accessory.

The housing 44 g may include first and second clamshells 50 g, 52 g thatmay be fastened together by a clip 53 g, other fasteners, or by a snapfit, for example. The second clamshell 52 g may be substantially similarto the first clamshell 50 g. Accordingly, except as otherwise provided,references to the first clamshell 50 g will be understood to applyequally to the second clamshell 52 g, and like reference numerals willbe used hereinafter and in the drawings to identify similar features andcomponents on both the first and second clamshells 50 g, 52 g.

The hub portion 130 g may include a retainer 48 g. The retainer 48 g mayinclude an arm portion 190 and a key feature 80 g. The arm portion 190may include a proximal end 194, a distal end 196, an inner surface 198and an outer surface 200. The proximal end 194 of the arm portion 190may be coupled to the hub portion 130 g. In this regard, in someconfigurations the arm portion 190 may be integrally and monolithicallyformed with the hub portion 130 g. The arm portion 190 may extend in acircumferential direction about the hub portion 130 g, such that theinner surface 198 of the arm portion 190 may be flush with the innersurface 136 g of the hub portion 130 g, and the outer surface 200 of thearm portion 190 may be flush with the outer surface 138 g of the hubportion 130 g.

The key feature 80 g may be coupled to the distal end 196 of the armportion 190 and may extend radially inwardly. In this regard, the keyfeature 80 g may include a radiused or arcuate surface 204 and aradially extending stop surface 206. The stop surface 206 may begenerally planar. The key feature 80 g and the arm portion 190 may beseparated from the hub portion 130 g by a peripheral space or void 208.In this regard, the retainer 48 g may be flexibly coupled to the hubportion 130 g, such that the arm portion 190 and/or the key feature 80 gcan flex or otherwise bend within the void 208 relative to the hubportion 130 g.

The collar 128 g may have a generally cylindrical construct including aninner surface 170 g and an outer surface 172 g. The inner surface 170may include a lock portion 176 g and a groove or channel 212. In thisregard, the channel 212 may at least partially define the lock portion176 g, such that the lock portion 176 extends radially inwardly relativeto the channel 212. In some configurations, the inner surface 170 g mayinclude two channels 212. In this regard, it will be appreciated thatthe number of channels 212 may correspond to the number of retainers 48g. The channel 212 may include a proximal end 214 and a distal end 216.The distal end 216 of the channel 212 may open into the distal end 168 gof the collar 128 g.

In an assembled configuration, the collar 128 g may be coupled to thehousing 14 g. In this regard, the collar 128 g may be slidably disposedabout the hub portion 130 g of the first and second clamshells 50 g, 52g, such that the channel 212 is aligned with at least a portion of theretainer 48 g. As will be explained in more detail below, in a firstposition, the channel 212 may be radially and axially aligned with thekey feature 80 g of the retainer 48 g.

In operation, the accessory 14 g can be assembled to the power tool 12by aligning the key feature 80 g with the corresponding recesses 42 ofthe power tool 12, and pushing or otherwise moving the accessory 14 galong the axis 26 relative to the power tool 12 until the key feature 80g is aligned with the neck portion 32 of the power tool 12. To securethe accessory 14 g to the power tool 12, the user can rotate theaccessory 14 g about the axis 26, such that the key feature 80 g isaligned with one of the indexing features 38. As the user rotates theaccessory, the retainer 48 g can flex or bend within the void 208 suchthat the key feature 80 g can disengage a first indexing feature 38 andengage a second indexing feature 38. In this regard, the channel 212 canallow the retainer 48 g to flex in a radially outward direction, suchthat at least a portion of the retainer 48 g may enter, or otherwise bereceived by, the channel 212. In this way, the user can change theposition of the tool subassembly 46 relative to the power tool 12 byselecting a desired indexing feature 38, or combination of indexingfeatures, to receive the key feature 80 g.

With the collar 128 g in a first or unlocked position (FIG. 15A), thechannel 212 may be aligned with the key feature 80 g of the retainer 48g, such that the retainer 48 g may flex or bend in the manner describedabove. In this regard, it will be appreciated that in the unlockedposition, the accessory 14 g may be rotatable on the power tool 12 aboutthe axis 26. To lock the accessory 14 g relative to the power tool 12,and thereby prevent the accessory from rotating about the axis 26, theuser can slide or otherwise move the collar 128 g along the axis 26 intoa second or locked position (FIG. 15B). In the locked position, the lockportion 176 g of the collar 128 g may engage, or otherwise be alignedwith, the outer surface 200 of the retainer 48 g, such that at least aportion of the retainer 48 g is no longer aligned with the channel 212.In this regard, the lock portion 176 g of the collar 128 g can preventthe retainer 48 g from flexing in a radially outward direction, suchthat the key feature 80 g is secured within the indexing feature 38, andthe accessory 14 g is prevented from rotating about the axis 26 relativeto the power tool 12. The contact between the key feature 80 g and theindexing feature 38 provides the user with tactile and/or audiblefeedback, which indicates that the attachment is in an orientation thatthe collar 128 g can be moved into the locked position.

With reference to FIGS. 16-18B, another accessory 14 h is provided thatmay be used with the power tool 12 instead of the accessory 14.Accessory 14 h may include a housing 44 h, a retainer 48 h, and a collar128 h. The structure and function of the housing 44 h, retainer 48 h andcollar 128 h may be similar or identical to the structure and functionof the housing 44 f, retainer 48 f and collar 128 described above, apartfrom any exceptions described below and/or shown in the figures.Accordingly, similar features will not be described again in detail.Like reference numerals are used hereinafter and in the drawings toidentify like components, while like reference numerals containingletter extensions are used to identify those components that have beenmodified. While not necessarily shown in FIGS. 16-18B, it will beappreciated that the housing 44 h may be shaped, sized and/or otherwiseconfigured to accommodate any shafts, gears, tools and/or other featuresof a given type of accessory.

The hub portion 130 h of the first and/or second clamshells 50 h, 52 hmay include an inner surface 136 h and an outer surface 138 h. The outersurface 138 h may extend axially from the housing 44 h, and may includea first groove or channel 150 h, the second groove or channel 152, and athird groove or channel 210. The third channel 210 may extendcircumferentially about the outer surface 138 and intersect the firstchannel 150 h. In this regard, the third channel 210 may extend in adirection substantially perpendicular to the first channel 150 h, asillustrated in FIG. 16.

The aperture 142 h may extend through the first and third channels 150h, 210. In this regard, the aperture 142 h may be located where thefirst channel 150 h intersects the third channel 210. The aperture 142 hof the first clamshell 50 h may be offset from the second mating surface56 h of the first clamshell 50 h by a first angle α1. The aperture 142 hof the second clamshell 52 h may be offset from the second matingsurface 56 h of the second clamshell 52 h by a second angle α2. Thefirst angle α1 may be substantially equal to the second angle α2.Accordingly, as illustrated in FIG. 17, in an assembled configuration,the aperture 142 h of the first clamshell 50 h may be substantiallyaligned (i.e., in a plane) with the aperture 142 h in the secondclamshell 52 h. In some configurations, the first and second angles α1,α2 may each be substantially equal to forty-five degrees. In thisregard, the tool 89 may include an axis of rotation 215. The axis ofrotation 215 and the axis 26 may define a plane 217. In the assembledconfiguration, the first and second mating surfaces 54 h, 56 h may besubstantially aligned with, or otherwise disposed in, the plane 217,such that the aperture 142 h of the first clamshell 50 h is offset fromthe plane 217 and the axis of rotation 215 by the first angle α1 in aclockwise direction, and the aperture 142 h of the second clamshell 52 his offset from the plane 217 and the axis of rotation 215 by one hundredeighty degrees, less the second angle α2, in a counterclockwisedirection.

The retainer 48 h may include a substantially U- or C-shaped construct,extending from a first end 216 to a second end 218. The retainer 48 hmay include a key feature 80 h. As illustrated, in some configurations,the retainer 48 h may include two key features 80 h. In someconfigurations, the key feature 80 h may be monolithically formed withthe retainer 48 h from a singular piece of material. In this regard, theretainer 48 h may be formed from spring steel, or other suitablyflexible material, and the key feature 80 h may define a substantiallyU-shaped, radially inwardly projecting portion of the retainer 48 h. Inas assembled configuration, the retainer 48 h may be disposed within thethird channel 210 such that the key feature 80 h is aligned with, andextends into, the aperture 142 h. In this regard, in the assembledconfiguration, a first of the key features 80 h may be offset from theplane 217 and from the axis of rotation 215 by the first angle a1 in theclockwise direction, and a second of the key features 80 h may be offsetfrom the plane 217 and from the axis of rotation 215 by one hundredeighty degrees, less the second angle α2, in the counterclockwisedirection.

The collar 128 h may include a radially inwardly projecting lock portion176 h. In this regard, the lock portion 176 h may project radiallyinwardly from the inner surface 170 h of the collar 128 h. Asillustrated in FIGS. 18A and 18B, in some configurations, the collar 128h may include two lock portions 176 h. With reference to FIG. 16, thelock portion 176 h may include opposed lock surfaces 184 h. The locksurface 184 h may taper radially inwardly. In this regard, the locksurface 184 h may be concave or otherwise include a cylindrical profile,such that the profile of the lock surface 184 h mirrors a profile of thekey feature 80 h.

In an assembled configuration, the collar 128 h may be coupled to thehub portion 130 h of the first and second clamshells 50 h, 52 h. In thisregard, the collar 128 h may be slidably disposed about the hub portion130 h, such that the lock portion 176 h is received in the first channel150 h, and the retainer 48 h is secured between the inner surface 170 hof the collar 128 h and the outer surface 138 h of the hub portion 130h.

In operation, the accessory 14 h can be assembled to the power tool 12by aligning the apertures 142 h, and thus the key feature 80 h with thecorresponding recess 42 of the power tool 12, and pushing or otherwisemoving the accessory 14 h along the axis 26 relative to the power tool12 until the key feature 80 h is aligned with the neck portion 32 of thepower tool 12. To secure the accessory 14 h to the power tool 12, theuser can rotate the accessory 14 h about the axis 26, such that keyfeature 80 h is offset from the recess 42 about the axis 26. In thisregard, the user can rotate the accessory 14 h until the key feature 80h is aligned with one of the indexing features 38, such that the usercan change the position of the tool subassembly 46 relative to the powertool 12 by selecting a desired indexing feature 38, or combination ofindexing features, to receive the key feature 80 h. As the user rotatesthe accessory 14 h, the retainer 48 h may bias or otherwise bendradially outwardly, such that the key feature 80 h moves radiallyoutwardly. In this regard, when the key feature 80 h is offset from theindexing feature 38, the key feature may be substantially flush with theinner surface 136 h of the hub portion 130 h, such that the key feature80 h does not extend radially inwardly beyond the inner surface 136 h.

With the collar 128 h in a first or unlocked position (FIG. 18A), thelock portion 176 h may be axially offset from key feature 80 h. In thisregard, the lock portion 176 h may be disposed between the key feature80 h and the fifth stop surface 148 h of the hub portion 130 h along theaxis 26. To lock the accessory 14 h relative to the power tool 12, andthereby prevent the accessory from rotating about the axis 26, the usercan move the collar 128 h along the axis 26 into a second or lockedposition (FIG. 18B). In this regard, as illustrated in FIGS. 16, 18A and18B, the accessory 14 h may include a biasing member 220, such acompression spring or detent (not shown), for example. The biasingmember 220 can urge or otherwise move the collar 128 h along the axis 26and into the locked position when the user releases the collar. Thecontact between the key feature 80 h and the indexing feature 38provides the user with tactile and/or audible feedback, which indicatesthat the attachment is in an orientation that the collar 128 h can bemoved into the locked position.

In the locked position, the lock portion 176 h may apply a radiallyinward force on the key feature 80 h, thus securing the key feature 80 hwithin the aperture 142 h and into engagement with the indexing feature38. As will be appreciated, the user can overcome the force of thebiasing member 220 to move the collar 128 h back into the unlockedposition, thus allowing the user to rotate the accessory 14 h relativeto the power tool 12 and/or remove the accessory 14 h from the powertool 12.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail.

What is claimed is:
 1. A power tool comprising: a motor; an output shaftdriven by the motor; a neck portion configured to receive a removableattachment accessory; and a collar portion supported by the neckportion; wherein the neck portion defines a first diameter and includesa plurality of indexing features; wherein the collar portion has anouter circumferential surface defining a second diameter that is greaterthan the first diameter; wherein the outer circumferential surface hasat least one recess; wherein the collar has at least two recesses;wherein the at least two recesses are disposed on opposite sides of thecollar; and wherein the plurality of indexing features comprises aplurality of recesses separated by peripheral surface portions.
 2. Thepower tool of claim 1, wherein the at least one recess is aligned withone of the plurality of indexing features.
 3. The power tool of claim 1,further comprising a removable attachment accessory, wherein theremovable attachment accessory includes a retainer having a radiallyinwardly extending key feature and the plurality of indexing featuresare configured to selectively engage the key feature.
 4. A power toolcomprising: a motor; an output shaft driven by the motor; a neck portionconfigured to receive a removable attachment accessory; and a collarportion supported by the neck portion; wherein the neck portion definesa first diameter and includes a plurality of indexing features; whereinthe collar portion has an outer circumferential surface defining asecond diameter that is greater than the first diameter; and wherein theouter circumferential surface has at least one recess; furthercomprising a removable attachment accessory, wherein the removableattachment accessory includes a retainer having a radially inwardlyextending key feature and the plurality of indexing features areconfigured to selectively engage the key feature; wherein the recess isconfigured to allow the key feature to be moved past the collar.
 5. Thepower tool of claim 1, wherein the power tool is a drill or ascrewdriver.
 6. A power tool accessory comprising: a housing defining aninner chamber, the housing configured for removably coupling theaccessory to a power tool; and a retainer at least partially disposedwithin the inner chamber, the retainer having an inwardly projecting keyfeature configured to engage the power tool; wherein the accessoryincludes a hub and a collar slidably supported by the hub.
 7. The powertool accessory of claim 6, wherein the retainer is resiliently flexible.8. The power tool accessory of claim 6, wherein the retainer issubstantially U-shaped.
 9. The power tool accessory of claim 8, whereinthe key feature is substantially U-shaped.
 10. The power tool accessoryof claim 6, wherein the housing includes first and second clamshells,the first clamshell having first and second pockets, and the secondclamshell having third and fourth pockets aligned with the first andsecond pockets, respectively, and wherein the retainer includes a firstmember at least partially disposed in the first and second pockets, anda second member at least partially disposed in the third and fourthpockets.
 11. The power tool accessory of claim 6, wherein the collarincludes a radially inwardly extending lock portion operable to lock theretainer in a first position.
 12. A power tool assembly comprising: ahousing having a neck portion and a collar portion, the neck portionincluding a first outer surface defining a first diameter and having aplurality of indexing features formed therein, the collar portionincluding a second outer surface defining a second diameter greater thanthe first diameter; a motor; an output shaft supported by the housingand driven by the motor, the output shaft defining an axis of rotation;and an accessory removably coupled to the output shaft, the accessoryincluding a retainer, the retainer having a radially inwardly extendingkey feature disposed between the housing and the collar; wherein thecollar includes a recess through which the key feature may pass; whereinthe accessory includes a hub and a collar slidably supported by the hub;and wherein the collar of the accessory includes a radially inwardlyextending lock portion operable to lock the retainer in a firstposition.